prosch



(No Model.) E'Sheets-Shee't 1.

O. P-ROSOH.

SHUTTER FOR 'PHOTOGRAPHIO GAMBRAS.

Patented Nov. 2,1886.

wmmssns: B 'IifVBNTQR:

ATTORNEYS.

u, PETERS, FhaloUkhognplwr. Washmglun. nc.

(No Model.) 2 Sheets-Sheet 2. O. PROSGH.

SHUTTER FOR PHOTOGRAPHIO-GAMBRAS No. 352,098. Patented Nov. 2, 1886.

fz i b ATTORNEYS.

N. PETERS. Pbflla-Lilhu rapber, Wm 0.0.

UNITED STATES PATENT OFFICE.

CYRUS PROSQH, OF NEW YORK, N. Y., ASSIGNOR TO THE PROSOH MANU- FACTURINGCOMPANY, OF SAME PLACE.

SHUTTER FOR PHOTOGRAPHIC CAMERAS.

SPECIFICATION forming part of Letters Patent No. 352,098, dated November2, 1886.

(No model.)

To all whom it may concern.-

Be it known that I, CYRUS PROSOI-I, of the city, county, and State ofNew York, have invented a new and useful Improvement in Shut ters forPhotographic Cameras, of which the following is aspecification,reference being had to the annexed drawings, forming apartthereof, in which- Figure 1 is a front elevation of my-improved shutter.Fig. 2 is arear elevation. Fig. 3 is a plan view. Fig. 4 is an interiorview of the shutter-case, showing the shutter in a closed position. Fig.5 is an enlarged rear View. Fig. 6 is an enlarged inverted plan view.Fig. 7 is an enlarged front View showing one of the positions of theshutter in dotted lines. Fig. 8 is an enlarged front view showing theshutter in another position in dotted lines. Fig. 9 is a partial planview showing the actuatinglever of the shutter mechanism.

Similar letters of reference indicate corresponding parts in thedifferent figures of the drawings.

The object of my invention is to provide an easily-regulated shutter forphotographic cameras which can be readily used to make eitherinstantaneous or time exposures, and which is capable of the greatestrapidity of operation with the least possible jarring of the camera, andalso to provide a trigger or release for same which shall operate easilyunder the strongest pressure of the motive-spring.

My invention consists in apair of apertured shutters pivotedin a caseintersecting the camera-tube, and arranged to swing past each other toopen and close the camera-tube, and in a spring-actuated lever arrangedto operate both shutters simultaneously; also in an escapement ofpeculiar construction arranged to retain or release the lever.

It also consists in an arrangement of parts whereby the escapement maybe adjusted so as to allow the shutters to make only half-of theirexcursion for each impulse of the releasing mechanism, so that theshutters may be opened by one impulse and closed by another, to secure atime exposure.

It also further consists in a pneumatic device for operating theescapement.

The camera-tube A is intersected by a thin casing, 13, of curvilineartriangular form, in which are pivoted two sector-shaped shutters, O 0',upon the pivots a. The shutters O O are slotted at the points oppositetheir pivots in adjacent edges, and in the wider ends of the shuttersare trapezoidal openings 2). Between the trapezoidal openings 1) and theedges of the shutters solid parts a c and d d are left.

In the casing B, midway between the pivots a of the shutters O 0, thereis a slot, (2, and in front of the casing 13, near one edge thereof, ispivoted a lever, D, on a screw, f.

From the rear surface of the lever a pin, 9, projects through the slot 6and through the slots h in the shutters, so that the movement of thelever D up and down will cause the shutters O O to move in oppositedirections past each other. D a stud, 1', projects through a hole in thecasing 13, and is engaged by a spring, E, formed of a straight part,j, aspiral, k, wound around the stud Z, and the arm at, extending forwardover a curved notched bar, F,secured to the back of the casing B. Byplacing the arm at of the spring E in one or the other of the notches ofthe curved bar F the pressure of the spring E upon the stud i can bevaried.

The lever D is provided in its free end with a rectangular notch, 12,and a spring, 0, secured to the outer side of the lever by a screw, p,is provided with an aperture, g, which receives the grooved end of aninternallythreaded sleeve, 0*, which turns on the threaded stud s,projecting at right angles from the outer face of the lever D. The freeend of the spring carries a triangular stud, t, which in its normalposition is opposite the center of the notch a in the end of the leverD. The end of the spring 0,'betwee11 the screwp and the pivot of thelever D, is reduced in width to admit of the lateral turning of thespring within certain limits, and the narrower end of the spring isreceived in the slot of the stud 0, projecting from the face of thelever D.

Near the free end of the lever D, and in a sleeve, u, projecting fromthe back of the easing B, is journaled a shaft, 22, having on its outerend a stud, w, of triangular form, with one of its angles near thecenter of the shaft. The shaft 2;, on the outer side of the casing B,

Near the pivot of the lever is provided with a hand-lever, to, havingone end arranged so that it may be operated by the hand, and having inthe other end a slot, 11.

On the back of the casing B is secured'a small pneumatic cylinder, 0,which is open at one end, and is closed at the other by a tubulatedplug, (1, which receives a rubber tube, 0, communicating with a flexiblebulb, f. In the open end of the cylinder 0 is inserted a cylindricalpiston, g, which projects beyond the end of the cylinder, and isprovided with a stud, h, which extends through the slot t" in the casingB, and is received in the slot 1/ of the lever a. A stop, is secured tothe front of the casing, for limiting the upward motion of the lever D.

The bulbf, by which air is compressed to transmit motion to the pistong, is provided with an eyelet, 7c, in one end thereof, which is providedwith a very small aperture to allow a very small quantity of air toescape from the bulb, to create a quite complete vacuum, which isrequired when a time exposure is to be made.

In one side of the camera-tube A, at the side of the casing B, is formeda slot, H, in which is inserted an oblong diaphragm-plate, G, having anaperture of any desired size. The plate G projects beyond the side ofthe tube A, over the surface of the casing B. and a screw, 1, passingthrough the casin g B, bears against the side of the diaphragm-plate G,and holds it in its position in the tube.

The operation of my improved shutter is as follows: When it is desiredto produeean instantaneous exposure of the photographic plate, thespring E is put under sufficient compression to cause the lever D andthe shutters G 0, connected therewith, to move with the desiredrapidity. The lever D is then depressed until it is brought into contactwith the triangular stud w, projecting from the end of the shaft 1). Theshaft 1; is then turned, by means of the lever a, until the lever Dpasses the stud to, when the shaft 1; is returned to its originalposition, with the triangular stud 20 above the lever D, as shown inFig. 5. In moving thelever D downward the solid parts d d of theshutters will be moved away from each other, causing the trapezoidalopenings b to pass each other and bring the solid parts 0 opposite theopening of the cameratube, closing the tube. \Vhen the shutters are inthis position, the lever is depressed to its lowest point. The longerface of the triangular stud w rests upon the top of the lever D, as

shown in Fig. 5. The end of the lever D exerts a pressure in a line withthe center (or nearly so) of the shaft oa dead-center. The camera havingbeen adjusted and focused, and the sensitive plate having been placed inthe camera, the shutters having been closed in the manner described, thecamera is ready for the exposure of the plate. This is effected bycompressing the bulb f in the hand, forcing the air into the cylinder 0,pushing up the piston g,which, by its engagement with'the lever athrough the stud h, turns the lever to, and the shaft 2;, to which it issecured, carrying the stud over the end of the lever D, allowing thelever to escape, when the spring E presses the lever upward, and thelever, by its engagement with the shutters O 0, turns them on theirpivots, causing the shutters to pass each other, bringing thetrapezoidal openings 7) opposite each other for an instant, and finallyclosing the opening of the cameratube by bringing the solid parts (Z ofthe shutters opposite each other, closing the tube, as indicated inFigs. 1 and 2.

The speed of the closing of the shutters may be varied by increasing thepressure of the spring E, by raising the arm of the spring at andretaining it in a raised position by bringing it into engagement withone of the upper teeth of the notched bar F.

\Vhen it is desired to make a time exposure, the spring ois movedforward toward the face of the lever D, bringing it near the face of thelever without touching it, by turning the threaded sleeve 1'. Thisoperation brings the triangular stud topposite the center of the notcha. When it is desired to make a time exposure, the motive-spring E isplaced at a low tension. The lever D is depressed and brought to alocked position, as for an instantaneous exposure. The spring 0, whichis now in the position shown in Fig. 3,. is then brought close to theface of the lever D, as shown in Fig. 9, by turning the threaded sleeve1'. This brings the triangular stud t in a position to engage with thestud w on the release-shaft c.

When it is desired to make the exposure of the plate, the bulb f iscompressed, forcing the piston g outward, turning the lever a and thestud w, allowing the lever D to escape from the stud, and to make halfof its upward excursion, the lever being arrested at the moment thetrapezoidal openings 1) coincide by the engagement of the triangularstud with the stud t,proj ecting from the back of the spring 0.Immediately after the compression of the bulb f it is allowed to quicklyexpand, producing a partial vacuum, which draws back the piston 9 intothe cylinder 0, turning the lever a into the position of starting,bringing the triangular stud into engagement with the end of the leverat the lower side of the notch n, as shown in Fig. 7. When in the upwardmovement of the lever D it is arrested by the engagement of the stud towith the stud t, projecting from the spring 0, the spring 0 yieldssufficiently to bring the upper surface of the stud t, projectingtherefrom, even with the lower side of the notch, so that the transferof the triangular stud w from the stud t to the end of the lever at thelower side of the notch does not permit the lever D to move. The spring0 then resumes its normal position. This operation is very materiallyaided by the eyelet or vent in the air-bulb f, which, when the bulb iscompressed, allows the escape of air from it, creating a very perfectvacuum in the bulb, tube, and pistoncylinder, which, when the bulb isquickly allowed to expand, as the air can re-enter the vent but veryslowly, op-

crates with much force on the piston 9. After the plate has been exposeda suflicient length of time, the bulb f isagain compressed, forcing thepiston 9 out of the cylinder 0, thereby turning the lever a. and thestud w in the manner already described, allowing the end of the lever Dto escape from the stud w and close the shutters by bringing the solidparts (1 d of the shutters opposite the opening of the tube, as in thecase before described.

By means of my improved shutters I am enabled to make instantaneousexposures, and am able to regulate the time of the exposure by varyingthe pressure of the spring E; and I. may readily adjust the parts so asto produce a time exposure of any desired length, and quickly open andclose the shutters at the beginning of the exposure.

it is obvious that other meansthan the pneumatic cylinder and bulb maybe employed for releasing the lever D, and, if desirable, the lever amay be turned by hand to release the lever D, thus obviating thenecessity of employing the pneumatic bulb and cylinder. It is alsoobvious that there are various other ways of applying the motive force.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

1. In a photographic-camera shutter, two similar shutters. O G,oppositely arranged with respect to each other and provided withtrapezoidal openings p, with solid portions 0 (Z, opposite sidesthereof, and having slots It formed radially with reference to thepivots of the shutters, and in the combination therewith of a pin, rinserted in both slots and arranged to move the shutters in oppositedirections, to effect the opening and closing of the aperture of thecamera by the continued movement of the pin h in one direction,substantially as herein specified.

2. In a photographic-camera shutter, the combination of the casing B,apertured shutters G 0, supported 011 pivots a in the casing, andprovided with slots h, arranged approximately at right angles with thearms of the shutters,in adjacent sides thereof, the lever D,

provided with the pin 9, projecting through the slot in the casing B andentering the slots h of the shutters, and means for moving the lever D,substantially as herein shown and described.

3. In a photographic-camera shutter, the combination of the casingB,shutters O O, pivoted therein and provided with slots h, the lever D,and pin y,projecting therefrom through the side of the casing B and intothe slots h of the shutters, the shaft '0, and triangular stud 10,carried thereby, and means for turning the shaft 22, substantially asherein shown and described.

4. In a photographic-camera shutter, the combination of the aperturedand pivoted shutters O 0, provided with slots h, the lever D, providedwith a pin, 9, projecting into the slots h of the shutter, the shaft '0,and stud w, projecting from the end thereof, the adjustable spring E,the slotted lever a, the pneumatic cylinder 0, and the piston 57, fittedthere to and provided with the stud h, projecting into the slot of thelever to, substantially as herein shown and described.

5. In a photographic-camera shutter, the casing B, the apertured andpivoted shutters G 0, provided with the slots h, the lever D, providedwith the pin 9, projecting into the slots of the shutter, the leverhaving formed in the end thereof a notch, n, the adjustable spring 0,carrying the stud t, the shaft 1;, and the triangular stud w, projectingfrom the end thereof, the adjustable spring E, and means for turning theshaft 2), in combination, substantiall y as herein shown and described.

6. The combination, with a pneumatic cylinder, c, of a camera-shutter,of the bulb f, provided with the eyelet 70, for the expulsion ofair tothe bulb, substantially as herein shown and described.

7. The combination, with the camera-tube A, of the casing B,intersecting the tube, the shutters O G, pivoted in the casing and provided with the slots h, the lever D, having studs 9 i, the adjustablespring E, and means for holding and releasing the lever D, substantiallyas herein shown and described.

8. In a photographicramera shutter, the combination of the tube A, thecasing B, intersecting the tube, the apertured and pivoted shutters G 0,provided with slots h, the lever D, pivoted to the casing B and carryingpins 9 i, the adjustable spring E, notched bar F, the adjustable spring0, provided with the stud t, the shaft 1), and triangular stud w,projecting therefrom, the slotted lever a, secured to the shaft 1), thepneumatic cylinder 0, and piston 9, working thereon and provided withthe pin 12, the flexible bulbf, provided with 4 \Vitnesses:

GEO. M. HOPKINS, O. SEnewIoK.

